Copied the dot cursor logic over from the Unix viewer incorrectly.

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4480 3789f03b-4d11-0410-bbf8-ca57d06f2519

vncviewer/Viewport.cxx

   for (i = 0; i < mask_len; i++)
     if (((rdr::U8*)mask)[i]) break;
 
-  if (i == mask_len) {
-    if (dotWhenNoCursor)
-      vlog.debug("cursor is empty - using dot");
+  if ((i == mask_len) && dotWhenNoCursor) {
+    vlog.debug("cursor is empty - using dot");
 
     Fl_Pixmap pxm(dotcursor_xpm);
     cursor = new Fl_RGB_Image(&pxm);